Combating oil fires



Patented Feb. 27, 1951 COMBATING OIL FIRES August W. Saxe and Vladimir A. Kalichevsky, Beaumont, Tex., assignors to Socony-Vacuum Oil Company, Incorporated, New York, N. Y., a corporation of New York No Drawing. Application October 19, 1948, Serial No. 55,428

2 Claims. (Cl. 1691) This invention relates to a method for combating oil fires and is particularly concerned with a novel step which makes it feasible to use water in extinguishing fires in liquid oils.

The problem of combating fires in large bodies of liquid oils, for example petroleum products, has long been a serious one. The only substance available in large quantities at low cost for this purpose is water, the disadvantages of which for this purpose are well understood. Since the water is of higher specific gravity than the oil, it tends to sink in the oil thus being removed from the actual flame area and rendered largely ineffective. Even more serious is the fact that, as the temperature of the body of oil approaches the boiling point of water, the water under the oil also reaches that boiling point and begins to evolve larg quantities of steam, forming froth which flows out of storage containers to form great areas of flaming oil.

It has been heretofore proposed that emulsifying agents be added to the water in order that the same shall be dispersed through the oil and 'thus cool th oil body below dangerous temperatures by evaporation of the water. Here again the problem of frothing arises with effects substantially the same as those where untreated water is used.

According to the present invention it has been found that oil fires may be successfully combated with water if a small quantity of an alkyl silicone polymer is first introduced to the oil body. This inhibits the tendency of the oil to froth upon agitation by steam evolved from the water. Even more important, it is found that steam bubbles break readily through the body of oil from boiling water beneath the oil and the evolution of steam is therefore a real advantage in that it blankets the flaming surface, removing the flame to such an extent that the oil can cool below dangerous levels. This exclusion of oxygen from the surface of the oil by means of steam which breaks through the oil surface is a major advantage of the present invention and it is contemplated that the water shall be used in quantities such that it will penetrate the oil and vaporize therein or therebelow to provide the desired steam blanket.

The alkyl silicone polymers are frequently added to oil products for the purpose of inhibiting tendency to foam upon agitation of the oil as when oil is supplied to a storage compartment, tank car or the like by a fill line which drops a stream into the container. Oils containing such material as an intended part of the finished proposition will not froth when water is applied to flame thereon and the invention is not directed to oils so treated.

Oils containing no or insufllcient quantities of alkyl silicone polymers to achieve the desired result are advantageously modified during fire fighting by hurling therein a glass container of the polymer, preferably dissolved in a light mineral oil fraction such as kerosene. Upon becoming heated in the fire, the container bursts releasing the agent into the body of oil.

In preferred embodiments, the invention contemplates provision of sealed glass containers of dialkyl silicone polymer dissolved in about an equal quantity of kerosene distributed about an area where petroleum products are handled or stored. The desired agent is thus preserved in suitable condition for use when fire occurs. Upon discovery of an oil fire, the fire fighter hurls one or more of the sealed containers into the body of oil and then directs a stream of water against the body of flaming oil.

When this practice is followed, it is found that the water vaporizes in and under the oil thus cooling the oil body and releasing steam which rises without frothing to the surface of the oil and provides a steam blanket which is constantly replenished as long as the oil remains at temperatures which will cause vaporization to feed the flames.

Suitable containers will contain five or ten ounces of silicone polymer solution as desired and are formed of thin walled glass similar to that used for incandescent electric light bulbs.

The alkyl silicones have received considerable attention in the literature in recent years and their structure is well understood. Preferred compositions according to the present invention are polymers of the relatively simple silicones such as dimethyl and diphenyl silicones. A preferred composition is a polymer of dimethyl silicone having a kinematic viscosity of 1000 centistokes at 25 C. and a specific gravity at that temperature of 0.973. This material has an average molecular weight of about 1400 and apparently corresponds approximately to the formula As an example of actual use of the present method in an oil refinery, a storage tank of motor gasoline caught fire. Sealed glass bulbs containing a per cent solution of the silicone polymer specifically described above were hurled into the storage tank in a ratio of 20 fluid ounces of polymer solution per thousand gallons of gasoline. Several streams from conventional flre hoses were then played against the flaming surface of the gasoline. Steam rising from vaporization of water in and under the gasoline immediately removed the flames to a point considerably removed from the top of the tank and the flre rapidly died out.

We claim:

1. In a process for combating a fire in a body of an organic oil, the steps which comprise introducing to the body of flaming oil a small amount of an alkyl silicone polymer in a ratio or at least one fluid ounce of said polymer per hundred gal- 1 lens of said oil and thereafter supplying water to the body of flaming oil.

2. In a process for combating a fire in a body of an organic oil, the steps which comprise hurling into a body of flaming oil at least one sealed glass container of a solution of alkyl silicone polymer in a light mineral oil fraction in a quantity to AUGUST W. SAXE. VLADIMIR A. KALICHEVSKY.

REFERENCES CITED The following references are of record in the I file of this patent:

UNITED STATES PATENTS Name Date 7 W Zimmer Apr. 12, 1949 Number 

1. IN A PROCESS FOR COMBATING A FIRE IN A BODY OF AN ORGANIC OIL, THE STEPS WHICH COMPRISE INTRODUCING TO THE BODY OF FLAMING A SMALL AMOUNT OF AN ALKYL SILICONE POLYMER IN A RATIO OF AT LEAST ONE FLUID OUNCE OF SAID POLYMER PER HUNDRED GALLONS OF SAID OIL AND THEREAFTER SUPPLYING WATER TO THE BODY OF FLAMING OIL. 